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Variable Intake Manifold, Checking






Variable Intake Manifold, Checking

Only perform the test if there is a loss of torque. That means there is a reduction in engine acceleration.

Special tools, testers and auxiliary items required

Hand vacuum pump (VAS 6213)

Test conditions:

The Intake Manifold Runner Control (IMRC) valve (N316) was checked with the vehicle diagnostic tester.

If the IMRC valve is OK, perform the following tests:

- Remove the engine cover.

- Start engine and let run at idle.

- Have a second person increase engine speed abruptly (press accelerator pedal). Observe the variable intake manifold vacuum actuator.

The actuator must activate - arrow -.






If change-over does not function as specified:

- Check the vacuum system for leaks.

- Check whether the change-over mechanism moves easily. Do this by actuating the linkage by hand.

- Check whether the vacuum lines are correctly connected.

- Check that vacuum hoses are not porous.

- Disconnect the vacuum hose - 1 - on the IMRC valve - 2 -.






- Set the slide ring - 1 - on the (VAS 6213) to the -A- position for "vacuum."






- Connect the (VAS 6213) to the IMRC valve actuator.






- Operate (VAS 6213) several times.

The vacuum actuator must move - arrows -.

- Replace the vacuum actuator if it does not move.